Agilex 7 non-RSU boot: how to configure SDM to use 4x redundant HPS SPL images starting QSPI addr 0?

Hi JingyangTeh, Thank-you for looking at this case.

>> By default the SDM will try out the next copy of the decision firmware once it finds that the first is corrupted.

Can you please confirm SDM will try the next copy when using a non-RSU layout, like the one shown here (so, there is just "Firmware", not "decision firmware"):
https://www.intel.com/content/www/us/en/docs/programmable/683673/23-3/standard-non-rsu-image-layout-in-flash.html

>> Could you please share the steps and command that you used to erase the QSPI flash?

1. Power cycle the device and verify boot succeeds.
As I understand, this indicates: SDM successfully loaded the FSBL into HPS RAM and released the HPS reset.
HPS ran the first stage bootloader, then the second stage bootloader.

2. When "Hit any key to stop autoboot: " is printed, press a key to stop the boot process in the U-Boot SSBL.

3. Verify the 4 images stored in SDM QSPI are all the same:
SOCFPGA_AGILEX # sf probe
SOCFPGA_AGILEX # sf read 0x02000000 0x0000000 0x00200000
SOCFPGA_AGILEX # cmp 0x02000000 0x02080000 20000
Total of 131072 word(s) were the same
SOCFPGA_AGILEX # cmp 0x02000000 0x02100000 20000
Total of 131072 word(s) were the same
SOCFPGA_AGILEX # cmp 0x02000000 0x02180000 20000
Total of 131072 word(s) were the same

4. Erase only the image at QSPI offset 0:
SOCFPGA_AGILEX # sf erase 0x00000000 0x80000

5. Power cycle the device.

result: The device does not boot -- No prints are seen on the HPS UART.